1. Field of the Invention
This invention relates to a drive device for an industrial truck, the drive device having a pivoted bolster that can rotate around a vertical axis, two drive wheels that are mounted on the pivoted bolster parallel and in mirror symmetry with respect to the vertical axis, and a device that is located between the drive wheels to generate a differential action between the drive wheels.
2. Technical Considerations
Drive devices with a pivoted bolster are used, for example, in industrial materials handling equipment. In such equipment, there is generally a single drive wheel. This type of construction has the disadvantage that high wear occurs to the wheels, particularly when the wheels are steered while the vehicle is stopped. Moreover, the steering forces that an operator must apply by means of a towbar are high.
DE 199 54 590 A1 describes a generic drive device that does not suffer from this disadvantage because it has two parallel drive wheels. In that case, the two drive wheels are coupled with a common electric motor that is located in the wheel hubs, into which a differential is integrated. Also installed in the wheel hubs are two reduction gearsets, each of which is connected to one of the outputs of the differential. As a result of the small amount of space available, this known configuration requires a very tightly packed and therefore complicated arrangement of the individual components of the drive device.
Therefore, it is an object of the invention to provide a drive device of the general type described above but that has a simplified construction.